Complete List of Terms and Definitions for Stats 8

Terms Definitions
y-axis response variable
Level = df + 1
systematic errors Problem in measurment system
response variable Experiment: variable that is measured
represtative data sample has relevent characteristics of the general population
scatterplots show the association between two quantitative variables measured on the same cases
Convenience Sampling design where individuals are chosen based on who is easily available
Experimenter bias Where the researcher treats the groups differently either intentionally or unintentionally. or have to use subjective judgement.
Variable a characteristic of an item or individual
Sample set of data drawn from the population
Pictogram uses pictures instead of bars to represent quantities. (Misleading)
standard error standard deviation of a distribution of a sample statistic
multimodal more than two peaks (three or more have equal highest value)
what is regression? clever correlations that can handle more than two continous variables or a categorical IV.
histogram uses bars, touching. uses same info as a grouped frequency distribution. interval or ratio scale.
Qualitative variables counting the number of people or objects that fall within categories.
random error error that has a random distribution and can be attributed to chance
Quantitative Bivariate The type of data required for regression analysis
What are instrumentation effects? changes in measurement throughout the study because of unfamiliarity with the assessment tool. or changes with the way measurement is interpreted.
Descriptive statistics summarize tendencies and characteristics of data. Inferential statistics use sample statistics to make inferences about the populations from which the samples were drawn. Inferential statistics are used for hypothesis testing. Define the distribution of sample means.
correlation doesn't change wehen we change... the unit of measure!
Placebo Effect The tendency of many human subjects to show a response even when administered a placebo
The mean is 0 and the standard deviation is 1. Define correlation coefficient
the larger the variance.... the harder it is to find the significant difference 
Standard error of x-bar A measure of the variability of the sampling distribution of x-bar ; estimates the standard deviation of the sampling distribution of x-bar ; computed using the formula: s / n .
Law of Large Numbers The fact that the average (x bar) of observed values in a sample will get closer and closer to mu as the sample size increases
why do formal research in psych? so we can test and justify our claims and its what distinguishes psych from other social sciences.
What does the test of an interaction tell us? the main effect of each Iv on the DV and the sig of the interaction itself.